Irrational Anxiety

Recently, I was thinking about social anxiety and I realized that I have no external reason for feeling this way. I realize that anxiety is not rational, and that we are all our own biggest critics, but I wish that the positive feedback I have received would help my self-esteem more.
We had to do our annual reviews at work, and I basically evaluated myself as being competent to do my job--I didn't really go into a lot of detail about how wonderful I am (everyone I work with has expressed their dread of having to talk about themselves at evaluation time). My boss evaluated me higher and has frequently complimented my ability to provide excellent customer service and ability to remain calm (or, at least, appear calm, since normally, I'm freaking out inside).
Over the course of most of my life, I have also been told by numerous people that I am really smart (since my brother is probably a genius--literally, though he has never had an IQ test, by comparison, I don't feel all that intelligent). At least 3 people have told me I have a decent singing voice. Several people have complimented my appearance (in general, I feel okay about my appearance, and I have some qualities that I even like).
Only one person has ever called me stupid (an ex, who's opinion of me doesn't matter at all--he is the same person who told me I should lose 10 pounds when I weighed 115). My mom told me that I have a "flat voice," but she can't sing well, either. My dad has told me that I was an ugly baby (I agree--I looked like an alien), and both my parents have mentioned that they thought I was going to be "slow" and that I was not a very fun or personable child (again, compared to my adorable, brilliant, entertaining brother, I didn't stand a chance).
So, in summation, I don't have much of a reason to worry about judgement from others, and even when people seem impressed with my performance, I doubt my abilities. If I didn't second-guess myself so much, maybe I'd accomplish more and actually believe their praise...

I'm really happy to hear that Lilmutegirl (I think a name change is on order!). I think we all know deep down that our fears are irrational, but when you really start to see the principle as a reality in your own life, that's when you turn a corner. So I think this is that turning point for you. All the best

Anxiety is only rational if there's an actual threat. The fight or flight response was rational for our ancestors (you never knew if that rustling in the bush was a bird or a lion) but you don't really have that threat lurking at every corner nowadays. Irrational anxiety makes you perceive certain dangers that are probably illogical, yet they can ruin your life depending on your attitudes, the things you CHOOSE to believe.

I feel perhaps relying on the opinions of others is in the least tenuous, and at most disastrous to one's self-esteem. The accuracy of any statement should be put into context of the speakers own perspective. People unwittingly project their own emotional problems, carelessly harming others. For example, a mother may call a child fat, when in fact they themselves were emotionally abused or perhaps influenced by media.

Science points to many reasons for SA including genetic, developmental, environmental, and biochemical. Maybe what people with SA need is acceptance in our formative years, instead of the deliberate forcing of behaviors that do not come naturally to some of us, and often don't work in the real world.

Maybe I'm off topic, but I understand what you feel. It seems that resilience to the relentless onslaught of people's opinions may benefit the SA group. As an observation, it is possible that many people with high self-esteem don't actually deserve it, but simply have it. Why is that?

Being unable to function is not natural, it's a very different thing to being introvert. Though painfully introvert I have been able to overcome quite a bit of my weaknesses by learning and applying what I have learned, and so have many millions before me. Do not be fooled by that fraudulent sector of the scientific community who have hijacked science itself, DNA does not always work the way they would have you believe and does not dictate who you are. There is a whole other agenda in that which goes well beyond the scope of this thread. It's simply a matter if will you or will you not face up yo the challenge, and as indicated by the OP that often means changing how you perceive yourself and others. It's one big learning curve, and we are all subject to the process regardless of where we start off and end.